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Glenn Department of Civil Engineering

Lowry Hall

Clemson, SC 29634

(864) 656 3000

Characterization of Portland Cement Concrete Coefficient

of Thermal Expansion in South Carolina

Report No: FHWA-SC-17-03

T. H. Dellinger

A. Poursaee

Submitted to the South Carolina Department

of Transportation

This research was sponsored by the South

Carolina Department of Transportation. The

opinions, findings and conclusions expressed in

this report are those of the author(s) and not

necessarily those of the SCDOT. This report does

not comprise a standard, specification or

regulation.

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1. Report No. FHWA-SC-17-03

2. Government Accession No.

3. Recipients Catalog No.

4. Title and Subtitle Characterization of Portland Cement Concrete Coefficient of Thermal Expansion in South Carolina

5. Report Date October 31, 2016 6. Performing Organization Code

7. Author(s) Trent H. Dellinger Amir Poursee

8. Performing Organization Report No.

9. Performing Organization Name and Address Glenn Department of Civil Engineering Clemson University Clemson, SC, 29631-0911

10. Work Unit No. 11. Contract or Grant No. SPR 722

12. Sponsoring Agency Name and Address South Carolina Department of Transportation P.O. Box 191 Columbia, South Carolina 29202

13. Type of Report and Period Covered Draft of Final Report, 2015-2016 14. Sponsoring Agency Code

15. Supplementary Notes 16. Abstract The South Carolina Department of Transportation (SCDOT) sough to regionally calibrate specific input parameters used by the Mechanistic Empirical Pavement Design (MEPDG) software. These properties include the coefficient of thermal expansion (CTE), compressive strength, and unit weight of typical SC concrete mixtures. Additionally, splitting tensile strength was included in the experimental program. Laboratory produced mixtures were tested to identify the effective CTE value of the cement paste, sand, and coarse aggregate compotes typically used in SC concrete pavements. A 25 percent cement replacement of type F fly ash and a single source of natural sand was used in the mortar component of the concrete mixtures. A total three coarse aggregate sources were used in the form of no. 57 crushed stone product or a 75:25 blend of no. 57 and no. 789 crushed stone. The CTE values of the individual phases (i.e. cement paste, sand and coarse aggregates), and concrete mixtures were measured. The resulting CTE of paste and sand was 7.3 and 5.910-6 in./in./F, respectively. The CTE of three coarse aggregates ranged from 2.96 to 3.83to-6 in./in./F. The range of average CTE values of the concrete was 4.82 to 5.3210-6 in./in./F. The magnitude of the CTE values were shown not to be directly related to the compressive strength. Field cored specimens were also taken from a section of SC 80 in Spartanburg county, SC, and analyzed. Three pavement slabs were arbitrarily selected along a 3.5-mi. pavement section. The targeted slabs were of the outside travel lane, with cores taken between the wheel paths at the leading end, middle, and trailing ends of each slab. There was not significant difference between the average CTE values of pavement slabs. The effective CTE of SC - 80 concrete pavement was determined to be 5.0510-6 in./in./F. The compressive strength and unit weight properties of the SC 80 specimens suggested that the laboratory produced concrete mixtures from the first part of this study were representative of the concrete pavements in South Carolina. 17. Key Words Coefficient of Thermal Expansion, CTE, MEPDG

18. Distribution Statement No restrictions. This document is available to the public through the National Technical Information Service, Springfield, VA 22161

19. Security Classif. (of this report) Unclassified

20. Security Classif. (of this page) Unclassified

21. No. of Pages

22. Price

Form DOT F 1700.7 (8-69)

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Disclaimer The contents of this report reflect the views of the authors who are responsible for the facts

and the accuracy of the data presented within. The contents do not necessarily reflect the official

views or policies of the South Carolina Department of Transportation and this report does not

constitute a standard, specification, or regulation.

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Acknowledgments This project was funded by the South Carolina Department of Transportation and the

Federal Highway Administration. Their support is greatly appreciated. The authors would like to

acknowledge the assistance and feedback provided by personnel at the Office of Materials and

Research of the South Carolina Department of Transportation.

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Executive Summary With FHWA support, AASHTO recently officially adopted a new "mechanistic-empirical"

process for designing pavements in which nationally calibrated models are used to simulate and

predict pavement behavior that are best-fit approximations based on observations from across the

US and Canada. Unfortunately, the predicted pavement outcomes using national models may not

be accurate for specific locations. For this reason, virtually all states that use AASHTO pavement

design methods are most strongly encouraged to perform a calibration of the new pavement models

to local conditions. Because the new process is a complete break from the old procedure, the

design inputs are totally different and frequently based on properties that the Department has not

previously measured. While some inputs can be reasonably estimated, it is important to actually

measure key properties that have been found to have the greatest impact on design predictions to

ensure accurate pavement designs.

The South Carolina Department of Transportation (SCDOT) has desired to regionally

calibrate specific input parameter used by the Mechanistic Empirical Pavement Design (MEPDG)

software. These properties include the coefficient of thermal expansion (CTE), compressive

strength, and unit weight of typical SC concrete mixtures. Additionally, splitting tensile strength

was included in the experimental program.

This project determined the

CTE of the most common pavement

mixtures throughout the state of

South Carolina using AASHTO

T336-11 method. The data generated

in this project provided a

comprehensive overview of the CTE

of concrete mixtures in South

Carolina for direct implementation in

designing PCC pavement and for the

specification and testing of PCC

materials. Laboratory produced mixtures were tested to identify the effective CTE value of the

Images of slump measurements of laboratory mixtures

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cement paste, sand, and coarse aggregate compotes typically used in SC concrete pavements. A

25 percent cement replacement of type F fly ash and a single source of natural sand was used in

the mortar component of the concrete mixtures. A total three coarse aggregate sources were used

in the form of no. 57 crushed stone product or a 75:25 blend of no. 57 and no. 789 crushed stone.

The CTE values of the individual phases (i.e. cement paste, sand and coarse aggregates), and

concrete mixtures were measured. The resulting CTE of paste and sand was 7.3 and 5.910-6

in./in./F, respectively. The CTE of three coarse aggregates ranged from 2.96 to 3.8310-6

in./in./F. The range of average CTE values of the concrete was 4.82 to 5.3210-6 in./in./F. Results

indicated that the CTE values were not directly related to the compressive strength on the concrete.

The collected data were also used to calculate CTE values using the Tex-428-A method. Results

from the Tex-428-A method in all but one data set, showed lower CTE values compared to the

AASHTO T336-11 method. The maximum difference in CTE values between these test methods

was 0.13410-6 in./in./F.

Field cored specimens were also taken

from a section of SC 80 in Spartanburg county,

SC and analyzed. Three pavement slabs were

arbitrary selected along a 3.5-mile pavement

section. The targeted slabs were of the outside

travel lane, with cores taken between the wheel

paths at the leading end, middle, and trailing

ends of each slab. Results showed no significant

differences between the average CTE values of

pavement slabs. The effective CTE of SC - 80

concrete pavement was determined to be

5.0510-6 in./in./F. The compressive strength

and unit weight properties of the SC 80

specimens suggested that the laboratory

produced concrete mixtures from the first part of

this study were representative of the concrete

pavements in South Carolina.

Leading Trailing Middle

1

2

3

Map of sampling locations along SC 80 and Example of sampling locations within a slab

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Table of Contents Disclaimer .................................................................................................................................................... iii

Acknowledgments ........................................................................................................................................ iv

Executive Summary ...................................................................................................................................... v

Table of Contents ........................................................................................................